Fuel pump



April 5 1932- o. o. COLLINS 1,852,643

FUEL PUMP Filed April 17'. 1930 Pleated .ap-r. s, 1932 onu: osoNCOLLINS, or mvnnsmn, oamromvra,

' rum. Pour Application med April 17, 1930. Serial No. 445,158.l

'Ihis invention relates to fuel pumps, and' has for an object theprovision of a novel't 'of fuel pump, the operation of which is ependentupon the maintenance of a prede- 5 termined pressure in the lubricatingsystem of the engine with which the fuel pump is associated, therebyinsuring cessation of the' operation ofthe engine should failure of theoil pressure occur throughany cause.

Another objectis to provide simple and efficient means for automaticalland quickly priming the pump in the event t at the source of supplythereto has been permitted to 'become dry., l5 -Anothersobject is torovide a fuel ump in which the-pumping e ement is in t e form of adiaphragm having means associated therewith for reciprocating the centerportion thereof, with respect to' the plane of i' 2o its periphery, andin which the reciprocating means are so arranged that the reciprocationlof the center portion of the diaphragm extends to'equal distances uponoppositesides of that plane. n

25 A further object is to providey positive means for. easilydetermining the development `of any leak in the reciprocable, diaphragm.)e This invention possesses other objects and 30 advantageous features,some of which, with those enumerated, will be set forth .in thefollowing description of the inventions particular embodiment which isillustrated in the drawings accompanying and forming apart 35' of thespecification.

Referring to the drawings: Figure 1 is atop plan view of a fuel pump iembodying the principles of the present in vention. 4o

r sectional view.I

Fig. 3 is a horizontal that portionof the housin which contains thepumping mechanism.. he plane of sece tion isjindicated by the line a-3of Fig. 2,

:indthedirection of view by the arrows.

Y The fuel pumpof the present invention, isl 5 -3 'designed primarilyfor use `in conjunction with an internal combustion. motor such as ithat commonly employed'. for the propulsion by a plurality of cap screws7, to any con- 6, into the interior of the motor base, an

with the housing 6. A short arm 19 of the Fig. 2 is a longitudinal,vertical, medial sectionall view of of anautomtive vehicle. II wish itto be un.

of supplying fuel to substantially any type of engme usin li uid fuel.

The preferre em odiment of my improved fuel pump, comprises a housing 6adapted to be secured in any Aconvenient manner such as venient portionof the base 8 of the motor with which the fuel pump is associated. 'Apreferably circular boss 9 n a side of the housing 6, is adapted to seatwithin a 'complementary recess 11 in the motor base 8, so` as to hold anaperture 12 in that side of the housing 6 in register with an aperture13 in the motor'base,'so as to permit a rocker arm 14 to extend from theinterior of the housing establish suitable connection with a cam 16 70which is carried by a cam shaft 17 or any other' suitablecyclically-moving part of the motol, so as to effect periodicreciprocation of the rocker arm 14.

The rocker arm 14 is pivotally mounted upon a preferably horizontally'extendin stub shaft 18 which extendstransversely 0% the aperture 12,and which is preferably rigid rocker arm I4, extends beyond the stubshaftA 18 and ,carries a transversely extending bar 21 and a finger 22extending downwards to be engaged by a lcap or 'ferrule 23 which iscontinually urged upwards by means of a coil sprin 24 which is retainedin axial alignment with t e finger 22, by means of a central boss 26rigid with the bottom 27'of the housing 6. Due to the presence of thisspring 24, the finger 22 and arm 19I of the rocker arm 14, arecontinually urged upwards; with the result that-the opposite end 28 ofthe rocker arm 14, is at all times maintained in riding contact with thecam 16. 1

Also pivotally mounted upon the stub aft 18, is a crank arm 31. That end32 fof the crank rm 31, which is pivoted upon the shaft 18, isbufurcated (see Fig. 3) and the -only connection between the crank arm31 and the rocker arm 14, is through the exsurface of the bifurcated end32 of the crank arm 31. Hence, movement of the bar 21 downwards, causescorresponding downward pivotal movement of'the crank arm 31; but upwardretraction of the bar 21 does not cause the return stroke of the crankarm 31. Instead, upward movement of the crank arm 3l is dependent upon acoil spring 33 which is interposed between a cap or ferrule 34 and theupper side of a piston 36. The cap 34 engages a finger 37 at the bottomend of a reciprocably mounted rod 38 to which the outer end of the crankarm 31 is joined. Any convenient means may be employed' for joining thecrank arm 31 to the rod 38-for example, the outer end 39 of the crankarm 31 may also be bifurcated t'o engage upon opposite sides of the rod38 and to permit a pin 41 to extend through the bifurcated end 39 andthrough a .suitable aperture in the rod 38. In view of the rotary motionof the crank arm 31 during reciprocation thereof, it will be necessarywhen such connecting means are employed, tdenlarge laterally theaperture in the rod 38 and/0r the apertures in the bifurcated end' 39 ofthe crank arm 31, to permit that amount of lateral movement of the end39 of the crank arm 31 with respect to the rod 38 which is coincidentwith the reciprocation of these two elements.

The piston- 36 upon which the spring 33 is supported, forms the upperwall of a pressure chamber 46 which is formed in the bottom 27 of thehousing 6. A suitable conduit 47 leads from the inlet 48 of the chamber46, to 'the pressure lubricating system of the engine with which thepump is associated; and the partsare so .proportioned and arranged thatthe piston 36 is adapted to be forced upwards by oil 49 within thechamber 46 when the pressure of the oil in the lubricating system ismaintained at a predetermined value. Upward movement of the piston 36 islimited by means of a ferrule 51 threaded onto the upper end o'f anannular extension 52 of the side walls of the pressure chamber 46. Iprefer to employ some suitable type of sealing means such as a pistonring 53 to establish a substantially leak-proof seal between the piston36 and the boreof the chamber Y46, al-

' though no serious consequences will resultfroma limited amount ofleakage of oil from the chamber 46 into the interior of the housing 6 ofthe pump, inasmuch as any oil which chamber 58 is formed. A diaphragm 59eX- f tends transversely of the chamber' 58, being retained in operativeposition by having the periphery thereof,"compressed between the head 56and the upper end of the chamber 6; The center portion of the diaphragm59 is engaged between opposed plates 61 and 62 which are rigidlyconnected with the upper end of the rod 38 through the expedient of anut 63 or its equivalent. Hence, reciprocation of the rod 38 producescorresponding reciprocation of the center portion of. the diaphragm 59;and in order to provide guiding means for the reciprocation of theseparts, the rod 38 is slidably retained within a cylindrical guide 64extending downwards from the top of the housin 6.

A bleeder hole 66 establishes communication between the exterior of thehousing 6 and the chamber 58 below the diaphragm 59.

The outlet from the pump chamber 58 is by way of a conduit 67 whichleads to the carburetor of the engine, or to whatever means forutilizing fuel are employed. This conduit 67 is connected by means of aconventional union fitting 68, to a valve chamber 69 above a valve plate71 which is pressed downward upo'n its seat 72, by means of a spring 73which is under com ression between the valve plate 71 and a p ug 74which is threaded into the upper end of the valve chamber 69. Below thevalve plate 71 the valve chamber 69 enters the pump chamber 58 above thediaphragm 59, i. e., upon the opposite side thereof from that with whichthe bleeder hole 66 communicates.

A lateral extension 76 of the head 56, supports a supply reservoir 77which preferably serves as a sediment trap. A bail 78 pivotally joinedto the extension 76, extends around the b ottom end of the trap 77 andcarries a threaded pin 79 upon which a thumb nut 81 is threaded. Thisnut 81 may be screwed upwards against the bottom of the trap 77, topress the trap upwards against a gasket 82 to establish a tight sealbetween the upper end of the trap 77 and the under face of the extension76 of the head 56.

Communication is established between the trap 77 and the pump chamber 58through the expedient of a passage 83 and a second valve chamber 84. Thepassage 83 enters the chamber 84 above a valve plate 86 which is presseddownwards against its seat 87 by means of a spring 88 which is undercompression between the valve plate 86 and a valve plug 89 which isthreaded into the upper end of the valve chamber 84. Below the valveplate 86 a draught-tube 91 is threaded into the valve seat 87, thisdraught-tube 91 extending downwards into the trap 77 and preferablybeing provided at its lower end, with a strainer 92.

The inlet to the sediment trap 77 is by way of a conduit 96 which leadsfrom the asoline-tank or whatever source of liquid uel is employed, andisconnected to the extension 76 of the head 56, by means of a "v107,tovertical movement; and a stop conventional union fitting 97. Theentrance 98 of the fitting 97 into the extension76, communicates withthe interior/of the tra '77v preferably by means of a tube 99 whicAextends downwards therefroml a'. material distance into the trap 77. li

. Means afre also provided for pri1ning`the fuel ump. A conduit 101leading from any suifta le area of relatively low pressure, such forexample, as the intake manifold of the engine with which the fuelpump-is asso-A ciated, is connected by means of a union fitting 102 to apassage 103' in the extension. 76. This passage 103'communi'ca-tes witha preferably removable valve seat 104 having a-relatively small aperture106 extending therethrough into the passage 103. A needle valve 107 isassociated with the valve seat4 104, and is rigidly connected to a float108 which is disposed inside thetra 77 adjal which in one directioniscaused by the downward movement of the arm 31coincident with rotation ofthe cam l'againstthe-end 28 of the rocker arm 14,' an'd the returnstroke of which is caused -by the spring 33, causes the center portionof the diaphragm 5'9'to move- -the same distance above the plane of theperiphery of the diaphragm .upon the upstroke,

f as the distance below that plane which this portion'ofthe diaphragmmoves upon the `ldownstroke thereof. In' this manner, the

maximum stroke of thev centerportion of the diaphragm, is vattained with.a minimum amount of distortion thereof from trueplanar arrangement, ascompared with the more usual manner of utilizing a diaphragm' pumpingmember whereinthe` diaphragm at one end of its stroke, liessubstantially flat` and at the Aother end of its stroke 'is distorted vto permit the center portion of the diaphragm the bottom ofl itslstroke, whereasthe dashed tially r theupperfextreme of its stro to liein a plane spaced from the plane of the periphery, a distance equal tothe maximum stroke. The full line position ofthe diaphra 59 upon Fig. 2,indicates the position of t ediaphragm when at substantlally lineposition indicated at 59', show'ssubstanthe position of the dia hragmwhen at Operation I' I Y. Iif, for lanjy'vreasonyth-e sediment .trap 77filled or primed as soon* as the crankshaft -of the engine starts toturn, because of the vacuum developed in the intake manifold by thepumping action ofy the pistons of that engine.- Inasmuch as the conduit101'communicates with the intake manifold or some f other part of the:mechanism wherein an area of low pressure exists, under suchcircumstances, air .will be drawn past the needle v valve 107 andthrough the conduit 101. However, the only inlet to the sediment trap77, is through the conduit'96 which leads from the gasoline-tank becausethe spring- 'pressed valve plate 86r precludes the possibil- 1;1ty ofentrance into the sediment trap 77 by way of the passage 83. `Accordinglgasoline or 'whatever liquid -fuel is beii'igemlployed, will be drawnthrough-the conduit 96 and into the sediment trap 77. This flow of' fuelintothe trap 77 will continue, provided rotation of the crankshaft iscontinued, until A the level of the liquid within the trap 77 hasreachedthat height which results in floating the float 108 suiiicientlyto bring the valve 107 into seatingengagement with the valve seat V 104.This is the normal position of the valve 107 and float 108, it beingunderstood that these parts become displaced\fro1n this position onlywhen the liquid within the trap 77 has fallen below a predeterminedlevel.

In this manner, a sucient quantity of liquid fuel isautomaticallymaintained within the trap 77, so. that the lower end ofthe vdraught-tube'91, is immersed therein. Con-v sequently, thedownstroke ofthe diaphragm"l 59, will cause "a givcnquantity of thisfue] to be drawn past the check valve 86, through.

the passage 83, and into that\p or tion ofthe'. f

pump chamber 58 which isabove the dia- 59. As soon as the downstrokeof?l the diaphragm ceases, the check valve 86 will;` be seated vby itsspring 88; with the resultV that the upstroke of the diaphragm 59,causes E the ejection of the same vamount ,of fueLas Y that which waspreviously drawn into the* chamber, this 'ejection occurring however, vpast the check'valve 71, and thence intothe -fuel line 6 7. The partsareso pro ortioned* and arranged that the length of t e-stroke.-

of the diaphragm, is just suicient tosupply the'maximum amount of fuelwhich will'b'e. necessary for the satisfactory operation of the motorVunder any circumstances.

ly,-thi s' reciprocation of the diaphragm, oc-g...

As wiuleadny be understand, reap-meal .ld-

curs `ati-all times that the crankshaft of the.'VU v motor is rotating,inasmuch as there is a suit-aV able interconnection (not shown) between,(j the erankshaftand the cam shaft 17. The v Y engagement of the end 28of the rockerarm fl 14 with the cam 16, causes lateral tion of the end28 and vertical reciprocation l 65j has been, emptied, it l.willautomatically befpqfthe short arm 19 ',`andY thzt the.f'barg'21.

Inasmuch as the bar 21 rests upon the'A upper face of a portion of thecrank arm 31, downward movement of the bar 21, will cause similardownward movement of the crank arm 31, resulting in drawing the centerportion of the diaphragm 51, downwards. As soon as the crest of the cam16 has passed its line of contact with the rocker arm 14, elevation ofthe bar 21 will commence, with the result that the spring 33 will thencause the return stroke of the rod 38 and the center ortion of thediaphragm 59,' provided a Su cient pressure is imposed upon the oil 49within the chamber 46, to retain the piston 36 at its position ofmaximum elevation against the counterthrust of the spring 33. In theevent that the pressure lubricating system of the engine has failed fromany cause, the pressure imposed upon the oil 49 within the chamber 46,will be relieved, permitting the piston 36 to drop, whereupon the spring33 will be unable to push the rod 38 upwards to cause the return strokeo f the diaphragm. Consequently,- the suppl of fuel to the motor, isdependent upon tli'e existence of .a predetermined pressure upon the oil49 within the chamber' 46; and whenever such pressure fails, the motorwill automatically be stopped through the failure of the delivery of asuffi- 'cient quantity of fuel to the carburetor.

It is to be understood that the details of the invention as hereindisclosed, are subject to alteration within the spirit or scope of theappended claims.

I claim:

1. In a fuel pump, a pumping member operable by reciprocation thereof,means for periodically moving said pumping member in one direction, apressure chamber adapted to receive Huid under ressure, a wall of saidchamber being movable and responsive to variation of pressuretherebehind, and rneans supported on said movable wall for moving saidmember in the other direction.

2. In a fuel pump, a pumping member operable by reciprocation thereof, apressure chamber, means connecting said chamber to a pressurelubricating system, a will of said chamber being movable with respect tothe remainder of said chamber and responsive to pressurechanges-therein, spring means interposed between said movable wall andsaid pumping member for moving the pumping member in one direction, andmeans for periodically withdrawing said pumping mem- .ber against theyaction ofsaid spring means.

3. In combination with an internal combustion engine having a fuellintake and a pressure lubricating system; pumping means,

a conduit connecting said pumping means i a y f --wlth said fuel intake,a pressure chamber,

means connecting said pressure chamber to vsaid lubricating system, andmeans dependent upon the maintenance of a predetermined -pumping means,a pressure chamber, means connecting said chamber to said lubricatingsystem, a wall of said chamber bein movable with respect to theremainder of sai chamber and responsive to pressure changes therein,

spring means interposed between said mova le wall and said umping means,and means actuated by a cyc cally-moving part of said engine forwithdrawin said pumping means against'the action of said sprin means. v

5. In combination with an internal combustion engine having a fuelintake and a pressure lubricating system, reciprocable pumping means, apressure chamber, means lconnecting said chamber to said lubricatingsystem, a pistonreciprocable in said chamber, spring means interposedbetween said piston and said pumping means, and means actuated by aciclically-moving part vof said engine for wit drawing said pumpingmeans against the action of said sprlngmeans.

6. In a fuel pump a housing having a chamber, a diaphragm extendmgthereacross, valved inlet and outlet passages communicating with saidchamber on one side of said dia hragm, a rod rigid with said diaphragm,sai housing having a pressure chamber therein, means connecting saidpressure chamber to a source of fluid under` pressure, a pistonreciprocable within said pressure chamber,I a s ring interposed betweensaid piston and sai rod, and means for periodically movgsaid rod againstthe action of said spring.

In a fuel pump a housing having a chamber, a diaphragm extendingthereacross, valved inlet and' outlet passages communieating with saidchamber'on one side of said iaphragm, and means for reciprocati tionperpendicular to the normal plane therethe center portion of saiddiaphragm in a lrecof, the stroke of said center portion extending y vtoequal distances upon the opposite sides of the plane of the periphery ofthe diaphragm.

. 8. In a fuel pump a housing having a chamber, a diaphragm extendingthereacross, valved inlet Aand outlet passages communieating withsaid'chamber onone'side of said diaphragm, and means for reciprocatingthe center portion of said diaphragm, said housing having a bleederholepextending from the exterior thereof to said chamber on the otherside of said diaphragm. I

-9. In a fuel pump, pumping means, a sediment trap, a passage leadingfrom said sediment tra to said pumping means, a conduit leading rom saidtrap to a source of liquid fuel, and means for automatically primingsaid sediment trap to draw suicient fuel thereinto to fill the trapabovethe level of the entrance thereinto of said passage.

10. In a fuel pump, pumping means, a sediment trap, a passage leadingrom said sediment tra to said pumping means, a conduit leading rom saidtra to a source of liquid 4 5 fuel, a valve seat in the top of saidtrap, a

valve associated therewith, a float connected to said valve andadapted-to close the valve when the level of the fuel within said trapreaches a predetermined height, and a con I A duit leading from saidvalve seat to an area of relatively low pressure. I

11. In a fuel pump, a pumping member operable by reciprocation thereof,means for periodically moving said member in one di- 15 rection, 'apressure chamber adapted to receive fluid under pressuretand meansoperated by ressure within said chamber for moving sai lpumping means inthe other direction. i f v l v12. In a fuel pump, a pumping member op`erable by reciprocation thereof, vmeans for periodically moving saidmember in one di- A rection, a pressure chamber adapted to rep ceivefluid under pressure, means operated by pressure within id chamberformoving said pumpinganeansi the other direction, and re-v silientmeans interposed between said pressure-operated means and saidpumpingmem-v ber' to permit movement of saidl pumping 39 member by saidperiodically moving means 'against the action of said pressure-operatedmeans.- \je i3. In combination'with an internal com` bustionv enginehaving an` intake manifold, a carburetor, anda fuel supply conduit,pump- 'f ing means, a supply reservoir ,communicating with said pumpinmeans and vwith said conduit, a valve seat 1n the to of Asaid"reservoir, a valve associated therewit ,a iioat connected 40 to saidvalve and adapted to close the valve v when the -level of the fuelwithin said reservoir reaches a predetermined height, and a conduitleading'from said valve seat to said manifold.

'45 In testimony whereof I have signed `my Y "name vto thisspecification.

oDIE osoN COLLINS.'

